Canadian Journal of Anesthesia/Journal canadien d'anesthésie

doi: 10.1007/BF03005985pmid: N/A

Samuelson, Paul; Merin, Robert; Taves, Donald; Freeman, Richard; Calimlim, Jose; Kumazawa, Teruo

doi: 10.1007/BF03005975pmid: 971456

Seven obese and five normal weight patients were studied before, during and after one hour of methoxyflurane-nitrous oxide anaesthesia during peripheral surgical operations and compared with eight patients of normal weight anaesthetized with nitrous oxide-meperidine and d-tubocurare. Estimates were made of renal function, including serum and urinary electrolytes, osmolarity, uric acid, urea and Creatinine. Renal clearances for the latter three substances were also calculated. Serum and urinary inorganic and organic fluoride concentrations were measured, as were renal clearances. This low dose methoxyflurane anaesthesia resulted only in a decrease in uric acid clearance among all the measures, when compared to the meperidine-nitrous oxide controls. The clearance of uric acid remained depressed for longer in the obese patients, but otherwise they did not differ from the normal weight patients. It is possible but not proven that depressed uric acid clearance may be related to the organic fluoride metabolite and an early indicator of methoxyflurane renal toxicity. The previously documented biotransformation of methoxyflurane was seen in this study. A double peak in serum inorganic fluoride was shown in all patients but one. Rather large differences in peak levels of serum inorganic fluoride occurred. The only significant difference between the obese and normal weight patients as far as fluoride metabolism was concerned was a greater variability in the serum inorganic fluoride levels in the obese patients. It would appear that the obese patient metabolizes methoxyflurane in a quantitatively if not qualitatively different fashion than the normal weight patient, perhaps because of fatty infiltration of the liver. Caution is advised in the use of methoxyflurane for more than 90 minutes of low concentration administration in view of the unpredictability of the biotransformation.

Lee, Chingmuh; Chen, Dennis; Barnes, Angeline; Katz, Ronald

doi: 10.1007/BF03005981pmid: 183877

The neuromuscular block produced by neomycin is unique. Despite nearly complete blockade of the twitch the tetanus is not blocked and does not fade. The pathognomonic post-tetanic exhaustion has not been reported previously. Anti-cholinesterases and calcium antagonize the block, but the antagonism may not be complete. Genuine antagonizes the block in the cat, but its clinical value has not been tested. These characteristics of neuromuscular block by neomycin strongly suggest respiratory support and sedation to decrease the respiratory drive, rather than attempts at antagonism, as the rational management of patients suffering from toxic paralysis due to neomycin.

Gillick, John

doi: 10.1007/BF03005982pmid: 971461

Over the past three years the inflation-catheter technique (ICT) of controlled ventilation during general anaesthesia has proved a safe and useful method for use with laryngoscopy and other trans-oral endoscopies (most notably flexible fiberoptic bronchoscopy). The ICT allows full control of the patient’s airway for the anaesthetist and exceptionally good exposure for the surgeon.

doi: 10.1007/BF03005987pmid: N/A

Stovner, J.; Innes, K.; Holen, A.

doi: 10.1007/BF03005980pmid: 971460

Data are presented on ten cases of anaesthesia-induced malignant hyperthermia in Norway. Seven of the patients died, three recovered. The fatal cases were all boys in the age group 11-20 years. This age and sex distribution suggests that puberty with the increase in androgens is a precipitating factor in malignant hyperthermia. One of the victims who survived was a 4 1/2-year-old pseudohermaphrodite girl with the adrenogenital syndrome. The coincidence of malignant hyperthermia in a patient with such a rare syndrome points to the excessive formation of androgens in patients with this syndrome as a predisposing factor.

Duffin, James

doi: 10.1007/BF03005986pmid: N/A

Greiss, Leila; Tremblay, N.; Davies, D.

doi: 10.1007/BF03005976pmid: 822927

Le nitroprussiate de soude est utilisé comme vasodilatateur puissant chez l’homme depuis 1929. A partir de communications à propos de trois décès reliés au NPS on retient: l’acidose grave et le taux de dosage élevé de nitroprussiate de soude. Ces derniers effets peuvent se rencontrer chez des cas de réponses anormales, non-mortelles au nitroprussiate de soude.

Knill, R.; Coscrove, J.; Olley, P.; Levison, H.

doi: 10.1007/BF03005973pmid: 971454

The effects of narcotics on ventilatory control were assessed in 13 adolescents and young adults. Both a narcotic and narcotic-phenothiazine significantly depressed the CO2 response curve. Using an occlusion pressure technique (Pm100) to evaluate those neuromuscular processes that generate forces acting on the ventilatory pump, it was found that narcotic agents reduced neuromuscular drive. In most subjects, narcotics had an additional action that contributed to the overall ventilatory depression. Using carbon dioxide to vary neuromuscular drive before and after drug administration at constant levels of neuromuscular drive the drugs reduced tidal-volume responsiveness of the pump. We conclude that narcotics impair ventilation through a combination of two effects; first, reduced neuromuscular drive, most probably due to central depression, and second, increased impedance of the ventilatory pump, most probably due to a decrease in chest-wall compliance.

Enright, A.; Moore, R.; Parney, F.

doi: 10.1007/BF03005983pmid: 1067140

Fifty Bain circuits were tested for contamination following single patient use. A contamination rate of 8 per cent was found. Two methods of resterilization were examined. Sterilization by activated glutaraldehyde proved unsatisfactory, while ethylene oxide sterilization was found to be an effective method which produced no detectable adverse physical or chemical alterations of the circuits.